Perception®

The personal progressive lens design - as individual as its wearer
By calculating the progressive lens design through wave fronts the higher order aberrations are minimised. This ensures that the lens wearer can immediately enjoy optimum natural vision in the near and distance ranges. The additional integration of the Listing’s Rule guarantees clear vision all the way to the periphery, especially in cases of high cylinders.

The benefits of individual parameters

What happens if the PD, VD and pantoscopic angle deviate from the standard parameters? The useable fields of vision change. It gets more difficult to use the near vision portion of the progressive lens. The customer's eyes quickly move into the area of aberration and no longer have clear vision.

Optimal design with individual parameters Deviating PD Deviating of VD and pantoscopic angle
  As a result of a too large or too small PD the visual field cannot be fully used. The eye moves more quickly into the blurred areas. The visual fields, especially in the near zone, are very limited. The sur- face astigmatism becomes larger and therefore very quickly seems blurred in the periphery.
     
  Orange = large PD = high convergence
Green = small PD = low convergence
 

The individual parameters for Perception®    

Pupil distance (Single-PD)

Vertex distance (VD)

Pantoscopic angle

Wrap angle

 
Calculation of progressive lenses with individual parameters

The ideal progressive lens with large left and right viewing zones and incorporating the customer parameters and refraction is calculated through online optimisation. An optimised surface design can then be produced:

Individual-PD: 32 mm Individual-PD: 34 mm Individual-PD: 36 mm
VD: 13 mm VD: 14 mm VD: 11 mm
Pantoscopic angle: 7° Pantoscopic angle: 8° Pantoscopic angle: 5°
Prescription: Prescription: Prescription:
Sph. +1,5 Cyl. -1,0 A 60° Add. 2,25 Sph. +1,5 Cyl. -1,0 A 60° Add. 2,25 Sph. +1,5 Cyl. -1,0 A 60° Add. 2,25
 
We recommend a video centration appliance for measuring the patient's specific centration data!